At one point during the recent weeklong round of distributed denial-of-service (DDoS) attacks on white-hat hacker site Metasploit, an anonymous hacker sent a blackmail message to Metasploit creator HD Moore.

"Some random guy [said], "Give me all of your source codes,'" says Moore, who employed various counter-attacks to the series of DDoS assaults, which he describes as more annoying than destructive. But after stringing the purported blackmailer along for a while in order to trace him, Moore discovered the email message had come from one of the bots in a botnet army that was flooding the Metasploit site. Moore says the email may have been from someone other than the DDoS attackers; either way, Moore had no intention of falling for the blackmail.

The DDoS attacks began around Feb. 6 against security sites Metasploit, Immunity, Milw0rm, and Packet Storm, when a botnet flooded the sites' domains with HTTP requests. After a few days, the attacks focused entirely on Metasploit. Moore says the DDoS' incoming connection exceeded 15 Mbps with SYN packets sent to the www.metasploit.com and metasploit.com domains.

"They would follow over to the new IPs I had made," Moore says of his attempts to change DNSes and evade the attackers.

But Moore remained undaunted, and even had a little fun with the attackers, who appeared to be novices, he says. "It didn't look like the folks behind it were particularly clever -- more like someone got access to their friend's botnet and went on an ego-stroking rampage," Moore says.

At one point, Moore decided to try using Google Sites, a free Web hosting service from Google, to mitigate the DDoS attack. It worked for a few minutes -- until Google Sites hit its page limit, Moore says.

With the help of other researchers, Moore was able to narrow down the culprit command and control (C&C) domains to three -- all out of Russia. The researchers then got one of the domains blackholed. All three of the domains are associated with botnets and malware distribution.

Most of the bots, meanwhile, were infected Windows XP machines based in Turkey.

Moore decided to give the remaining two C&C domains a taste of their own medicine. He ran a reverse: For about 24 hours, he pointed the two DDoS streams that were flooding Metasploit back onto the offending domains so that they were flooding their own C&C infrastructure, he says. "The flood showed no sign of stopping before, and I sure wasn't trying to negotiate with them," he says.

The DDoS attacks finally came to a halt last Thursday. To take the sting out of future DDoS attacks, Moore is working on configuring his domain settings to a more "granular" level -- placing the various Metasploit resources, such as the framework and SSL, on different domains. "That would make it easier to bring the service up and down [in the event of another attack]," he says. "I had mail on a different network [so it wasn't affected in the latest round of attacks], and our DNS servers were fine [as well]."

But Moore says he wouldn't be surprised if the DDoS attacks on Metasploit resumed. If and when that happens, he said he would also enlist the help of some botnet-fighting volunteer organizations at the onset of an attack.